Question

The hours of daylight, y, in Utica in days x from January 1, 2013 can be modeled by the equation y = 2.89sin(0.0145x-1.40) + 10.99. How many hours of daylight, to the nearest tenth, does this model predict for February 21, 2013?

Answer 1

Answer:

9.3 hours

Step-by-step explanation:

Given

$y = 2.89\sin(0.0145x-1.40) + 10.99.$

Required

Hours of sunlight on Feb 21, 2013

First, calculate the number of days from Jan 1, 2013 to Feb 21, 2013

$days = 52$

So:

$x = 52$

So, we have:

$y = 2.89\sin(0.0145x-1.40) + 10.99.$

$y = 2.89\sin(0.0145*52-1.40) + 10.99.$

$y = 2.89\sin(0.754-1.40) + 10.99.$

$y = 2.89\sin(-0.646) + 10.99.$

$y = 2.89*-0.6020 + 10.99.$

$y = -1.740 + 10.99.$

$y = 9.25$

$y = 9.3$ --- approximated